This has happened several times and it always happens on medium stands (And I only have one). I have plenty of ramp agents and vehicles to cope with demand.
However, the baggage loader seems to stick to the aircraft and won’t load baggage. On small stands where there is no loader, all is well.
Attached a pic showing the stuck aircraft, fully boarded and ramp agents happily walking around.
I turned commercial flights off after the plane was stuck for a day.